Note 1 - Organization, Basis of Presentation and Summary of Significant Accounting Policies (Tables)

12 Months Ended

May 28, 2017

Notes Tables

Comprehensive Income (Loss) [Table Text Block]

	Unrealized Gains on Cash Flow Hedge
Balance as of May 29, 2016	$	—
Other comprehensive income before reclassifications, net of tax effect		432
Amounts reclassified from OCI		—
Other comprehensive income, net		432
Balance as of May 28, 2017	$	432

Allowance for Credit Losses on Financing Receivables [Table Text Block]

	Balance at beginning of period		Adjustments charged to revenue and expenses		Write offs, net of recoveries			Balance at end of period
Year Ended May 31, 2015	$	516	$	—	$	(134	)	$	382
Year E nded May 29, 2016	$	382	$	63	$	(110	)	$	335
Year E nded May 28, 2017	$	335	$	519	$	(453	)	$	401

Revenue Recognition, Multiple-deliverable Arrangements [Table Text Block]

	Year E nded
	May 28, 2017		May 29, 2016		May 31, 2015
Recorded upon shipment	$	456,512	$	458,985	$	465,848
Recorded upon acceptance in foreign port		62,481		64,181		67,714
Revenue from multiple element arrangements		8,431		13,400		4,253
Revenue from license fees, R&D contracts and royalties /profit sharing		4,833		4,533		1,806
Total	$	532,257	$	541,099	$	539,257

Schedule of Inventory, Current [Table Text Block]

	Year Ended
	May 28 , 2017		May 29, 2016
Finished goods	$	11,685	$	12,165
Raw materials		10,158		9,855
Work in progress		3,447		3,515
Total inventories	$	25,290	$	25,535

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Year E nded
	May 28, 2017		May 29, 2016			May 31, 2015
Numerator:
Net income (loss) applicable to Common Stockholders	$	10,590	$	(11,641	)	$	13,544
Denominator:
Weighted average shares for basic net income (loss) per share		27,276		27,044			26,884
Effect of dilutive securities:
Stock options and restricted stock units		376		—			452
Weighted average shares for diluted net income (loss) per share		27,652		27,044			27,336
Diluted net income (loss) per share	$	0.38	$	(0.43	)	$	0.50

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Year E nded
	May 28, 2017		May 29, 2016		May 31, 2015
Options	$	1,230	$	1,352	$	561
RSUs		2,734		2,113		1,016
Total stock-based compensation	$	3,964	$	3,465	$	1,577

	Year E nded
	May 28, 2017		May 29, 2016		May 31, 2015
Cost of sales	$	485	$	405	$	142
Research and development		83		90		16
Selling, general and administrative		3,396		2,970		1,419
Total stock-based compensation	$	3,964	$	3,465	$	1,577

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Year E nded
	May 28, 2017			May 29, 2016			May 31, 2015
Expected life (in years)		3.50			3.38			3.25
Risk-free interest rate		1.08	%		1.09	%		1.00	%
Volatility		26	%		31	%		32	%
Dividend yield		0	%		0	%		0	%

Schedule of Effect of Significant Unobservable Inputs for Investment [Table Text Block]

	At May 28, 2017			At May 29, 2016
Revenue growth rates		4	%		4	%
Expense growth rates		4	%		4	%
Income tax rates		15	%		15	%
Discount rates		12	%		12.5	%

Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table Text Block]

	Impact on value of investment in Windset as of May 28, 2017
10% increase in revenue growth rates	$	6,900
10% increase in expense growth rates	$	(1,900	)
10% increase in income tax rates	$	(600	)
10% increase in discount rates	$	(4,500	)

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	Fair Value at May 28, 2017						Fair Value at May 29, 2016
Assets:	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
Interest rate swap (1)	$	—	$	688	$	—	$	—	$	—	$	—
Investment in non-public company		—		—		63,600		—		—		62,700
Total	$	—	$	688	$	63,600	$	—	$	—	$	62,700